DT770 Pro MMCX Adapter
thingiverse
Simple little adapter to fit an MMCX adapter into DT770 Pro's with no modding of the can other than removing the existing cable. Insert the adapter into the headphones, then drill the hole out to 5.5mm (measure the diameter of the MMCX adapter you buy), I went up in steps stating at 3mm just to make the drilling less aggressive.
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